This invention relates to demountable optical fiber connectors and/or optical fiber terminations therefor.
A particularly important consideration in the construction of a practical demountable optical fiber connector is the manner in which precise lateral alignment of two butted fiber cores is to be achieved.
One approach to this problem of lateral alignment is to mount the fiber ends in ferrules that are accurately sized and in which the fiber cores are accurately centered. The ferrules then serve as reference surfaces and two fiber ends may be brought into lateral alignment by holding the ferrules against the walls of a V-groove. The mounting of each fiber end in its associated ferrule may be done, for instance, by potting the fiber end in a resin filling the bore of a ferrule. With this approach there is first the problem of obtaining the initial alignment of the fiber and ferrule, and then the second problem of retaining the alignment while the resin is cured. Many alignment methods that are not purely optical involve alignment errors that can be cumulative. Thus, for instance, misalignment may be introduced because the inside and outside surface of the ferrule are not accurately concentric, and also because the fiber core is not accurately centered within its cladding. When these errors are added to that introduced by distortion occurring during resin curing, it is difficult if not impossible to get good yields of terminations satisfying the very stringent requirements of low loss connectors.